Papua New Guinea is often billed as The
Land of the Unexpected and it is certainly that. Five small
species of skinks with green blood are found here, the only green-blooded
land vertebrates in the world. But why would these small inoffensive
lizards evolve green blood? In 1968 research into the blood of green-blooded
skinks determined that the colouration was due to the presence of
a biliverdin-type pigment, like that found in bile. Mark has a theory
that this may make the lizards taste bitter and deter predators,
a once tried, never repeated experience for lizard-eating birds.
Dr Chris Austin is the only scientist in the world currently studying
green-blooded skinks and he has an alternative theory, one that
if correct, might lead to a cure for human diseases like jaundice,
or even malaria. Mark and Chris set out to scour the mountains and
WWII wreck strewn jungles of PNG in an attempt to locate three of
the five known green-blooded skink species and obtain blood samples
for analysis. But whose theory is closest to the truth?

The Yellow-footed green-blooded skink,
(Prasinohaema flavipes), is the largest and probably most widespread
member of the genus Prasinohaema.